package com.dodoke.ojserver.interceptors;

import com.auth0.jwt.JWT;
import com.auth0.jwt.algorithms.Algorithm;
import com.auth0.jwt.exceptions.*;
import com.dodoke.ojserver.bean.Users;
import com.dodoke.ojserver.config.Result;
import com.dodoke.ojserver.service.IUsersService;
import com.dodoke.ojserver.utils.JWTUtils;
import com.dodoke.ojserver.utils.PassToken;
import com.dodoke.ojserver.utils.UserLoginToken;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.lang.reflect.Method;

public class JWTInterceptor implements HandlerInterceptor {
    private static final String  SING = "!Q1@3W1e4r9%9T9^9Y";

    private IUsersService usersService;

    public JWTInterceptor(IUsersService usersService){
        this.usersService =usersService;
    }
    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object object) {
        String token = httpServletRequest.getHeader("token");// 从 http 请求头中取出 token
        // 如果不是映射到方法直接通过
        if(!(object instanceof HandlerMethod)){
            return true;
        }
        HandlerMethod handlerMethod=(HandlerMethod)object;
        Method method=handlerMethod.getMethod();
        //检查是否有passtoken注释，有则跳过认证
        if (method.isAnnotationPresent(PassToken.class)) {
            PassToken passToken = method.getAnnotation(PassToken.class);
            if (passToken.required()) {
                return true;
            }
        }
        //检查有没有需要用户权限的注解
        if (method.isAnnotationPresent(UserLoginToken.class)) {
            UserLoginToken userLoginToken = method.getAnnotation(UserLoginToken.class);
            if (userLoginToken.required()) {
                // 执行认证
                if (token == null) {
                    throw new RuntimeException("没有身份令牌，请重新登录");
                }
                // 获取 token 中的 user id
                String id = JWT.require(Algorithm.HMAC256(SING)).build().verify(token).getClaim("id").asString();
                System.out.println(id);
                Users users = usersService.findUserById(id);
                if (users == null) {
                    throw new RuntimeException("用户不存在，请重新登录");
                }
                // 验证 token
                JWTUtils.verify(token);
                //将验证通过后的用户信息放到请求中
                httpServletRequest.setAttribute("users", users);
                return true;
            }
        }
        return true;
    }
}
